1. Field of the Invention
The present invention relates to an automated sample extractor or feeder/inoculator for a vessel or conduit. This vessel or conduit can be a bioreactor or other similar equipment.
2. Description of the Background Art
Development of new or more efficient commercialization of existing products requires faster and more effective methods to measure process variables. This is particularly true in processes which require cell culture and fermentation processes conducted in bioreactors where the accuracy of measurements in the research and development are critical for achieving economic production of high purity and highly refined end products.
Some factors which must be controlled include temperature and pressure. These factors are easily measured by utilizing standard sensors. However, many other factors can be measured only by removing samples for external laboratory analysis. The frequency of sample extraction for testing and measurement, number of tests on each sample and the time constraints on the process vary widely as do the methods and equipment used to obtain the samples.
In most cases, measurement processes for variables do not lend themselves to in-situ measurement by remote sensors directly in the process. Instead, samples must be physically extracted from the process and examined and manipulated outside the vessel or conduit. Before this examination and manipulation process can be effectively carried out either in a manual or automated fashion, a safe, effective means of sample extraction must be made available. This sampling process must provide a product that is an accurate subsample of the process composition.
Furthermore, since prior art designs do not lend themselves to use in existing systems, substantial modification to the system is required. The apparatus needs to minimize or eliminate the dangers associated with the sampling process in an efficient and cost effective manner while providing quality, reproducible results in order to be of value for commercial application.
One danger which must be avoided is danger to the operator or environment. When working with samples and especially hazardous samples, it is necessary to remove or feed/inoculate a sample without endangering the integrity of the process, subsequent samples, the operator or the outside environment. Many prior art devices are unsatisfactory in this area.
Also, some prior art systems are not automated. Therefore, there is potential danger posed by human procedural errors and operator and environmental exposure. Accordingly, a need exists for an automatable apparatus with the capacity for independent verification of equipment operation built in.
The materials being sampled themselves are often expensive. Therefore, excessive removal of sample should be avoided.
When taking samples, it is often important to maintain an aseptic environment. It is important that contamination from previous sampling or from the environment not contaminate the current sample or the process being sampled. Loss of a sample run or contamination of the process can have extremely expensive ramifications. Therefore, it is important to obtain a sample without the sampling procedure causing contamination.
Many prior art devices permit accumulation or pooling of samples or cleansing medium. When the device is first used this may not create a problem; however, upon subsequent runs, the samples will be contaminated or at least diluted.
Additionally in the prior art, technology used for taking samples is generally unsatisfactory for feeding/inoculating the vessel or container.